Police believe suspect in the University of Idaho murders returned to the crime scene hours later, before 911 was called, affidavit says

• Police believe the suspect charged with killing 4 University of Idaho students returned to the crime scene hours later.
• Police tracked Bryan Kohberger's cell phone movement that day and saw that it returned to the students' home at 9:21 a.m.

Police believe the murder suspect charged with killing four University of Idaho students in the middle of the night in November returned to the scene of the crime the next morning.

Prosecutors have charged 28-year-old Bryan Kohberger with four counts of first-degree murder and one count of felony burglary in connection to the killings of 21-year-olds Madison Mogen and Kaylee Goncalves and 20-year-olds Ethan Chapin and Xana Kernodle.

He appeared in court in Idaho Thursday after being extradited from his hometown of Albright, Pennsylvania, where he was detained on December 30. A judge ordered him held him without bail.

Moscow police say in an affidavit that they were able to identify the suspect's phone number and vehicle during their investigation and later tracked their movements from November 12 to November 14. The killings took place in the early hours of November 13.

The suspect's phone arrived near the scene of the crime at 2:47 a.m. local time, at which point the phone stopped being operational, the affidavit states. It was turned back on at 4:48 a.m. and cellular resources showed it on the highway moving away from the scene shortly after.

At 9 a.m., police said the phone left the suspect's home, arriving at the crime scene at 9:21 a.m. and leaving again 11 minutes later, by 9:32 a.m.

The two surviving roommates in the home where the killings occurred did not call police until 11:58 a.m. that same day, despite one of them later telling police that she had seen a person in their home overnight.

That roommate said she was asleep around 4 a.m. when she woke up to what she thought was Goncalves playing with her dog.

After continuing to hear noises, including what she thought was Goncalves saying "someone's here," the roommate opened her bedroom door twice to check on what was going on, according to the affidavit.

The first time, she didn't see anything, she said.

She opened it again after hearing someone crying and a male voice say, "It's OK, I'm going to help you."

A nearby security camera picked up the sounds of crying, a dog barking, and a "loud thud" at 4:17 am, the affidavit says.

The roommate told police that the second time she opened her door, she saw "a figure clad in black clothing and a mask that covered the person's mouth and nose walking towards her," according to the affidavit.

She said the man, who she did not recognize, walked past her as she stood in a "frozen shock phase."

The roommate then locked herself in her bedroom as the man walked toward the back sliding glass door, she said.

The affidavit didn't include an explanation of why the roommate didn't call 911 at that time.